Wedged hepatic vein portovenography for assessment of Rex vein patency in children with extrahepatic portal venous obstruction.

BACKGROUND: Meso-Rex bypass is the surgical intervention of choice for children with extrahepatic portal vein obstruction (EHPVO). Patency of Rex vein, umbilical recessus of the portal vein, is a prerequisite for this surgery. Conventional diagnostic modalities poorly detect patency, while transjugular wedged hepatic vein portography (WHVP) accurately detects patency in 90%. OBJECTIVES: We aimed to assess Rex vein patency and portal vein branching pattern in children with EHPVO using transjugular WHVP and to identify factors associated with Rex vein patency. METHODS: Transjugular WHVP was performed in 31 children with EHPVO by selective cannulation of left and right hepatic veins. Rex vein patency, type of intrahepatic portal venous anatomy (Types A-E), and factors associated with patency of Rex vein were studied. RESULTS: The patency of Rex recess on transjugular WHVP was 29%. Complete obliteration of intrahepatic portal venous radicles was the commonest pattern (Type E, 38.7%) while Type A, the favorable anatomy for meso-Rex bypass, was seen in only 12.9%. Patency of the Rex vein, but not the anatomical pattern, was associated with younger age at evaluation (patent Rex: 6.6 ± 4.9 years vs. nonpatent Rex: 12.7 ± 3.9 years, p = 0.001). Under-5-year children had a 12 times greater chance of having a patent Rex vein (odds ratio: 12.22, 95% confidence interval: 1.65-90.40, p = 0.004). Patency or pattern was unrelated to local factors like umbilical vein catheterization, systemic thrombophilia, or disease severity. CONCLUSION: Less than one-third of our pediatric EHPVO patients have a patent Rex vein. Younger age at evaluation is significantly associated with Rex vein patency.

Assessment of liver function by gadoxetic acid avidity in MRI in a model of rapid liver regeneration in rats.

BACKGROUND: This animal study investigates the hypothesis of an immature liver growth following ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) by measuring liver volume and function using gadoxetic acid avidity in magnetic resonance imaging (MRI) in models of ALPPS, major liver resection (LR) and portal vein ligation (PVL). METHODS: Wistar rats were randomly allocated to ALPPS, LR or PVL. In contrast-enhanced MRI scans with gadoxetic acid (Primovist®), liver volume and function of the right median lobe (=future liver remnant, FLR) and the deportalized lobes (DPL) were assessed until post-operative day (POD) 5. Liver functionFLR/DPL was defined as the inverse value of time from injection of gadoxetic acid to the blood pool-corrected maximum signal intensityFLR/DPL multiplied by the volumeFLR/DPL. RESULTS: In ALPPS (n = 6), LR (n = 6) and PVL (n = 6), volumeFLR and functionFLR increased proportionally, except on POD 1. Thereafter, functionFLR exceeded volumeFLR increase in LR and ALPPS, but not in PVL. Total liver function was significantly reduced after LR until POD 3, but never undercuts 60% of its pre-operative value following ALPPS and PVL. DISCUSSION: This study shows for the first time that functional increase is proportional to volume increase in ALPPS using gadoxetic acid avidity in MRI.

Early portal vein thrombosis after hepatectomy for perihilar cholangiocarcinoma: Incidence, risk factors, and management.

AIM: To study the incidence, risk factors and management of portal vein thrombosis (PVT) after hepatectomy for perihilar cholangiocarcinoma (PHCC). PATIENTS AND METHOD: Single-center retrospective analysis of 86 consecutive patients who underwent major hepatectomy for PHCC, between 2012 and 2019, with comparison of the characteristics of the groups with (PVT+) and without (PVT-) postoperative portal vein thrombosis. RESULTS: Seven patients (8%) presented with PVT diagnosed during the first postoperative week. Preoperative portal embolization had been performed in 71% of patients in the PVT+ group versus 34% in the PVT- group (P=0.1). Portal reconstruction was performed in 100% and 38% of PVT+ and PVT- patients, respectively (P=0.002). In view of the gravity of the clinical and/or biochemical picture, five (71%) patients underwent urgent re-operation with portal thrombectomy, one of whom died early (hemorrhagic shock after surgical treatment of PVT). Two patients had exclusively medical treatment. Complete recanalization of the portal vein was achieved in the short and medium term in the six survivors. After a mean follow-up of 21 months, there was no statistically significant difference in overall survival between the two groups. FINDINGS: Post-hepatectomy PVT for PHCC is a not-infrequent and potentially lethal event. Rapid management, adapted to the extension of the thrombus and the severity of the thrombosis (hepatic function, signs of portal hypertension) makes it possible to limit the impact on postoperative mortality. We did not identify any modifiable risk factor. However, when it is oncologically and anatomically feasible, left±extended hepatectomy (without portal embolization) may be less risky than extended right hepatectomy, and portal vein resection should only be performed if there is strong suspicion of tumor invasion.

A prospective study of sequential hepatic vein embolization after portal vein embolization in patients scheduled for right-sided major hepatectomy: Results of feasibility and surgical strategy using functional liver assessment.

BACKGROUND: Hepatic vein embolization (HVE) added to portal vein embolization (PVE) can further increase future remnant liver volume (FRLV) compared with PVE alone. This study was aimed to evaluate feasibility of sequential HVE in a prospective trial and to verify surgical strategy using functional FRLV (fFRLV). METHODS: Hepatic vein embolization was prospectively indicated for post-PVE patients scheduled for right-sided major hepatectomy if the resection limit of fFRLV using EOB-magnetic resonance imaging was not satisfied. The resection limit was fFRLV: 615 mL/m2 for predicting post-hepatectomy liver failure. Patients who underwent sequential PVE-HVE (n = 12) were compared with those who underwent PVE alone (n = 31). RESULTS: All patients underwent HVE with no severe complications. Median fFRLV increased from 396 (range: 251-581) to 634 (range: 422-740) mL/m2 by sequential PVE-HVE. From PVE to HVE, both of FRLV (P < .001) and fFRLV (P = .005) significantly increased. The increased width of fFRLV was larger than that of FRLV after performing HVE. Median growth rate was 71.3 (range: 33.3-80.3) %, which was higher than that of PVE alone (27.0%, range: 6.0-78.0). All-cohort resection rate was 88.3%. Strategy of using fFRLV for the resection limit and performing HVE in patients with insufficient functional volume resulted in no liver failure in all patients who underwent hepatectomy. CONCLUSIONS: Sequential HVE after PVE is feasible and safe, and HVE induced possibility of further liver growth and its functional improvement. Our surgical strategy using fFRLV may be justified.

Significance of Skeletal Muscle Loss in Liver Hypertrophy in Patients Undergoing Portal Vein Embolization Before Major Hepatectomy: Assessment With Body Composition and Nutritional Indicators.

BACKGROUND/AIM: The relationship between body composition including skeletal muscle and liver hypertrophy initiated by portal vein embolization (PVE) for major hepatectomy has not been clarified. This study aimed to investigate the effects of skeletal muscle, body adipose, and nutritional indicators on liver hypertrophy. PATIENTS AND METHODS: Fifty-nine patients who underwent PVE scheduled for major right-sided hepatectomy were included. The skeletal muscle area of L3 as skeletal muscle index was calculated. The relationship between skeletal muscle loss and clinical variables was assessed. We also evaluated the relationship between >30% liver growth or >12% liver growth/week after PVE. RESULTS: Skeletal muscle loss was observed in 39 patients (66.1%) and associated with zinc deficiency, visceral adipose index, liver growth rate, and liver growth rate/week. Multivariate analysis indicated that future liver volume and skeletal muscle index were associated with >30% liver growth, and functional future liver volume and skeletal muscle index were associated with >12% liver growth/week. CONCLUSION: Loss of skeletal muscle, and a small future remnant liver volume, attenuates liver hypertrophy initiated by PVE. Strength building and nutritional supplementation may have positive effects on liver hypertrophy after PVE.

Echo Rounds: Intraoperative Doppler Assessment of Transjugular Intrahepatic Shunt Flow Using Transesophageal Echocardiography.

The use of intraoperative transesophageal echocardiography (TEE) to assess venous congestion of the liver due to right heart dysfunction is well established, predominately through the Doppler interrogation of the hepatic and portal venous waveforms. Transjugular intrahepatic portosystemic shunts (TIPSs) are artificial intraparenchymal tracts through the liver that are placed to decompress the portal circulation in the setting of portal hypertension, most commonly due to cirrhosis. Herein, we describe the Doppler interrogation of a TIPS using intraoperative TEE, and how changes in the transmitted portal venous waveform were used to assess the severity of tricuspid regurgitation and inform management. (A&A Practice. 2022;16:e01607.).

Resection of the Portal-Superior Mesenteric Vein in Pancreatic Cancer: Pathological Assessment and Recurrence Patterns.

OBJECTIVES: The portal vein (PV)-superior mesenteric vein (SMV) margin is the most affected margin in pancreatic cancer. This study investigates the association between venous resection, tumor invasion in the resected PV-SMV, recurrence patterns, and overall survival (OS). METHODS: This multicenter cohort study included patients who underwent pancreatoduodenectomy for pancreatic cancer (2010-2017). In addition, a systematic literature search was performed. RESULTS: In total, 531 patients were included, of which 149 (28%) underwent venous resection of whom 53% had tumor invasion in the resected PV-SMV. Patients with venous resection had a significant higher rate of R1 margins (69% vs 37%) and had more often multiple R1 margins (43% vs 16%). Patient with venous resection had a significant shorter time to locoregional recurrence and a shorter OS (15 vs 19 months). At multivariable analyses, venous resection and tumor invasion in the resected PV-SMV were not predictive for time to recurrence and OS. The literature overview showed that pathological assessment of the resected PV-SMV is not adequately standardized. CONCLUSIONS: Only half of patients with venous resection had pathology confirmed tumor invasion in the resected PV-SMV, and both are not independently associated with time to recurrence and OS. The pathological assessment of the resected PV-SMV needs to be standardized.

Liver Transection-First Approach in Hepatopancreatoduodenectomy for Hilar Cholangiocarcinoma: A Safe and Secure Technique for the Early Assessment of Curable Resection and Vascular Reconstruction.

BACKGROUND: Hepatopancreatoduodenectomy (HPD) is often indicated in the resection of cholangiocarcinoma but is associated with high mortality.1-3 From a risk-benefit perspective, HPD can be justified only when curative resection is achievable.4-6 METHODS: A liver transection-first approach is a surgical technique in which liver transection precedes pancreatoduodenectomy (PD) and skeletonization of the hepatoduodenal ligament in HPD. This approach enables an early assessment of resectability and curability. RESULTS: A 64-year-old with jaundice had a tumor located mainly in the proximal bile duct, spreading from the confluence of hepatic ducts (dominant in the left hepatic duct) to the intrapancreatic bile duct. The right hepatic artery and portal vein existed in close proximity to the tumor. HPD (left hemi-hepatectomy and subtotal stomach-preserving PD) with vascular resection was performed. After liver transection along the Cantlie line, the right Glissonean pedicle was collectively secured inside the liver. The right hepatic artery, right portal vein, and right hepatic duct (RHD) were isolated, and the feasibility of vascular reconstruction was confirmed. After the RHD was divided and the negative margin was confirmed, we proceeded to perform PD. The portal vein was reconstructed between the right portal vein and the portal vein trunk. The right hepatic artery was anastomosed to the second jejunal artery of the jejunal loop with the right gastroepiploic artery as an interposition graft. CONCLUSION: The liver transection-first technique in HPD facilitates early assessment of curability and resectability as well as a safe and secure manipulation and reconstruction of the hepatic artery and portal vein.

Optimal treatment strategies for hepatic portal venous gas: A retrospective assessment.

BACKGROUND: Hepatic portal venous gas (HPVG) generally indicates poor prognoses in patients with serious intestinal damage. Although surgical removal of the damaged portion is effective, some patients can recover with conservative treatments. AIM: To establish an optimal treatment strategy for HPVG, we attempted to generate computed tomography (CT)-based criteria for determining surgical indication, and explored reliable prognostic factors in non-surgical cases. METHODS: Thirty-four cases of HPVG (patients aged 34-99 years) were included. Necessity for surgery had been determined mainly by CT findings (i.e. free-air, embolism, lack of contrast enhancement of the intestinal wall, and intestinal pneumatosis). The clinical data, including treatment outcomes, were analyzed separately for the surgical cases and non-surgical cases. RESULTS: Laparotomy was performed in eight cases (surgical cases). Seven patients (87.5%) survived but one (12.5%) died. In each case, severe intestinal damage was confirmed during surgery, and the necrotic portion, if present, was removed. Non-occlusive mesenteric ischemia was the most common cause (n = 4). Twenty-six cases were treated conservatively (non-surgical cases). Surgical treatments had been required for twelve but were abandoned because of the patients' poor general conditions. Surprisingly, however, three (25%) of the twelve inoperable patients survived. The remaining 14 of the 26 cases were diagnosed originally as being sufficiently cured by conservative treatments, and only one patient (7%) died. Comparative analyses of the fatal (n = 10) and recovery (n = 16) cases revealed that ascites, peritoneal irritation signs, and shock were significantly more frequent in the fatal cases. The mortality was 90% if two or all of these three clinical findings were detected. CONCLUSION: HPVG related to intestinal necrosis requires surgery, and our CT-based criteria are probably useful to determine the surgical indication. In non-surgical cases, ascites, peritoneal irritation signs and shock were closely associated with poor prognoses, and are applicable as predictors of patients' prognoses.

Assessment of remnant liver function and volume after selective ligation of portal vein and hepatic artery in a rat model.

PURPOSE: To evaluate liver regeneration after selective ligation of portal vein and hepatic artery by 3D Computed Tomography in an experimental model. METHODS: Sixteen Wistar rats were randomized into four equal groups: Group I- control (sham), Group II- isolated selective ligation of the hepatic artery, Group III- isolated selective ligation of the portal vein and Group IV- combined ligation of portal vein and hepatic artery. Before procedure and five days after a 3D CT Scan was performed to analyze the hypertrophy, weight and function of the remnant liver. RESULTS: The largest regeneration rate and increase of weight in the hypertrophied lobe was detected in group IV, the first with an average of 3.99 (p=0.006) and the last varying from 6.10g to 9.64g (p=0.01). However, total liver weight and the R1 ratio (Hypertrophied Lobe Weight/Total Liver Weight) was higher in group III (P<0.001) when compared with groups I, II and IV and showed no difference between them. The immunohistochemical examination with PCNA also found higher percentages with statistical significance differences in rats of groups III and IV. It was possible to confirm a strong correlation between hypertrophied lobe weight and its imaging volumetric study. Liver function tests only showed a significant difference in serum gamma-glutamyltransferase and phosphorous. CONCLUSION: There is a largest liver regeneration after combined ligation of portal vein and hepatic artery and this evidence may improve the knowledge of surgical treatment of liver injuries, with a translational impact in anima nobile.

Computational Fluid Dynamics-Based Blood Flow Assessment Facilitates Optimal Management of Portal Vein Stenosis After Liver Transplantation.

BACKGROUND: Portal vein stenosis develops in 3.4-14% of split liver transplantation1-3 and its early detection and treatment are essential to achieve long-term graft survival,2-5 although the diagnostic capability of conventional modalities such as Doppler ultrasound and computed tomography is limited.1,4,5 METHODS: This study used computational fluid dynamics to analyze portal vein hemodynamics in the management of post-transplant portal vein stenosis. To perform computational fluid dynamics analyses, three-dimensional portal vein model was created using computed tomographic DICOM data. The inlet flow condition was set according the flow velocity measured on Doppler ultrasonography. Finally, portal vein flow was simulated on a fluid analysis software (Software Cradle, Japan). RESULTS: An 18-month-old girl underwent liver transplantation using a left lateral graft for biliary atresia. At the post-transplant 1-week evaluation, the computational fluid dynamics streamline analysis visualized vortices and an accelerated flow with a velocity ratio < 2 around the anastomotic site. The wall shear stress analysis revealed a high wall shear stress area within the post-anastomotic portal vein. At the post-transplant 6-month evaluation, the streamline analysis illustrated the increased vortices and worsening flow acceleration to reach the proposed diagnostic criteria (velocity ratio > 3:1).3,5 The pressure analysis revealed a positive pressure gradient of 3.8 mmHg across the stenotic site. Based on the findings, the patient underwent percutaneous transhepatic portal venoplasty with balloon dilation. The post-treatment analyses confirmed the improvement of a jet flow, vortices, a high wall shear stress, and a pressure gradient. DISCUSSION: The computational fluid dynamics analyses are useful for prediction, early detection, and follow-up of post-transplant portal vein stenosis and would be a promising technology in post-transplant management.

Assessment of remnant liver function and volume after selective ligation of portal vein and hepatic artery in a rat model

Abstract Purpose: To evaluate liver regeneration after selective ligation of portal vein and hepatic artery by 3D Computed Tomography in an experimental model. Methods: Sixteen Wistar rats were randomized into four equal groups: Group I- control (sham), Group II- isolated selective ligation of the hepatic artery, Group III- isolated selective ligation of the portal vein and Group IV- combined ligation of portal vein and hepatic artery. Before procedure and five days after a 3D CT Scan was performed to analyze the hypertrophy, weight and function of the remnant liver. Results: The largest regeneration rate and increase of weight in the hypertrophied lobe was detected in group IV, the first with an average of 3.99 (p=0.006) and the last varying from 6.10g to 9.64g (p=0.01). However, total liver weight and the R1 ratio (Hypertrophied Lobe Weight/Total Liver Weight) was higher in group III (P<0.001) when compared with groups I, II and IV and showed no difference between them. The immunohistochemical examination with PCNA also found higher percentages with statistical significance differences in rats of groups III and IV. It was possible to confirm a strong correlation between hypertrophied lobe weight and its imaging volumetric study. Liver function tests only showed a significant difference in serum gamma-glutamyltransferase and phosphorous. Conclusion: There is a largest liver regeneration after combined ligation of portal vein and hepatic artery and this evidence may improve the knowledge of surgical treatment of liver injuries, with a translational impact in anima nobile.

Pure Laparoscopic Living Donor Right Hepatectomy Using Real-Time Indocyanine Green Fluorescence Imaging.

INTRODUCTION: In recent decades, the quantitative and technological development of laparoscopic liver resection has resulted in an extension into the transplantation area.1,2 However, laparoscopic living donor hepatectomy is still in its infancy due to technical difficulties and extreme caution regarding donor safety.3 Several experienced major centers have demonstrated the feasibility and safety of laparoscopic living donor hepatectomy, and recent advances in laparoscopic imaging technology support this move.4 In particular, indocyanine green near-infrared fluorescence imaging helps determine the correct liver parenchyma anatomical resection and the exact point of bile duct division.4-6 This video demonstrates the technique of pure laparoscopic living donor right hepatectomy and the usefulness of indocyanine green fluorescence imaging. METHODS: The donor was a 32-year-old gentleman who decided to donate part of his liver to his wife who was suffering from viral liver cirrhosis and hepatocellular carcinoma. His BMI was 20.3 kg/m2 and the preoperatively estimated donor's right liver volume was 836 ml, representing 63.6% of his entire liver. With the recipient's weight of 57 kg, the graft-to-recipient weight ratio (GRWR) was 1.6%. The liver had classic hilar anatomy except that the right posterior intrahepatic duct was joined separately to the left main hepatic duct. The patient setting and the placement of the trocars were the same as for our conventional laparoscopic right hepatectomy technique.7 After right hepatic artery and portal vein isolation and clamping, 2.5 mg of indocyanine green was injected intravenously. RESULTS: Total operation time was 370 min and estimated blood loss was 150 ml without transfusion. Indocyanine green fluorescence imaging clearly demonstrated the anatomical demarcation between the lobes and visualized the running of the biliary tree. His postoperative course was uneventful, and he was discharged on postoperative day 7. CONCLUSION: Real-time indocyanine green fluorescence imaging may be particularly helpful for delineating the anatomical surgical plane and determining the appropriate division point of the hepatic duct during laparoscopic living donor hepatectomy.

Exploring the use of single-port surgery in the conservative management of hepatic portal vein gas: A case report.

RATIONALE: Hepatic portal vein gas (HPVG) is known as a sign of a lethal condition resulting from bowel necrosis. Recently, the detection rate of non-life-threatening cases of HPVG has increased due to the technological development of imaging, i.e., computed tomography (CT). However, it is difficult to determine accurately whether surgical treatment is necessary because of its lethal potential. PATIENT CONCERNS: A 74-year-old woman suddenly complained about lower abdominal pain and vomiting after an operation for cervical spondylosis myelopathy. Her vital signs were slightly unstable and she was perspiring and exhibited pallor. Muscular defense was not clear, though her abdomen was tender and slightly distended. DIAGNOSIS: CT results showed massive HPVG. However, laboratory investigation did not clearly indicate bowel necrosis. Also, a contrast-CT scan was not performed due to her chronic renal dysfunction and asthma. INTERVENTION: Exploration was performed by single-port surgery (SPS) instead of exploratory laparotomy. OUTCOME: This approach showed no ischemic bowel and so conservative therapies were undertaken with confidence. The HPVG disappeared 2 days later, and she recover completely from the illness. LESSONS: HPVG requires immediate and reliable decision for management. However, unnecessary exploratory laparotomy should be avoided. Hence, a novel strategy should be considered in light of innovative surgical procedures. Our experience suggested that SPS was useful as an exploratory tool for the management of HPVG.

Modification and establishment of CT criteria in preoperative assessment of portal venous invasion by hilar cholangiocarcinoma.

BACKGROUND: To compare the diagnostic performance of CT criteria and to establish a new model in evaluating portal venous invasion by hilar cholangiocarcinoma. METHODS: CT images of 67 patients with hilar cholangiocarcinoma were retrospectively reviewed. Modified Loyer's, Lu's and Li's standard introduced from pancreatic cancer were used to evaluate portal venous invasion with the reference of intraoperative findings and/or postoperative pathological diagnosis. A new model was constructed with modified Lu's standard and contact length between portal vein and tumor. RESULTS: The modified Loyer's standard, modified Lu's standard and Li's standard showed a sensitivity of 86.7%, 83.3%, 70.0%, a specificity of 89.4%, 95.7%, 95.7% and an accuracy of 88.6%, 92.0%, 88.1%, respectively. CT criteria performed better in evaluating left branch. The new model performed significantly better than any CT criterion or contact length, with a sensitivity of 95.0%, a specificity of 96.5% and an accuracy of 96.0%. CONCLUSIONS: Modified Lu's standard performed best in evaluating portal venous invasion by hilar cholangiocarcinoma among three CT criteria. The left branch invasion could be evaluated by CT criteria better than the right branch and the trunk of portal vein. The new mode significantly improved the diagnostic performance of portal venous invasion by hilar cholangiocarcinoma.

Serial Assessment of Growth Factors Associated with Liver Regeneration in Patients Operated with Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy.

BACKGROUND: There is limited knowledge about the mechanisms behind the unparalleled growth of the future liver remnant (FLR) linked to associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). In this study, liver regenerative markers were examined in patients subjected to ALPPS. METHODS: Ten patients with colorectal liver metastases treated with neoadjuvant chemotherapy and ALPPS were included. Plasma was sampled at 6 time points and biopsies from both liver lobes were collected at both stages of ALPPS. The levels of interleukin (IL)-6, hepatocyte growth factor (HGF), tumor necrosis factor-α, epidermal growth factor, and vascular endothelial growth factor in plasma were measured at each time point. Expression of mRNA for markers of proliferation and apoptosis was studied in the biopsies from both liver lobes taken at both stages. RESULTS: ALPPS resulted in a peak of IL-6 after stage 1 (p = 0.004), which decreased rapidly and did not increase again after stage 2. HGF also increased after stage 1 (p = 0.048), and the HGF levels correlated significantly with the degree of growth of the FLR before stage 2 (p = 0.02, r2 = 0.47). There was a correlation between peak levels of IL-6 and HGF (p = 0.03, r2 = 0.84). CONCLUSIONS: IL-6 and HGF seem to be early mediators of hypertrophy after stage 1 in the ALPPS procedure. The peak HGF plasma level correlates with the degree of FLR growth in patients subjected to ALPPS.

Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction: quantitative assessment of flow and perfusion changes using 2D-perfusion angiography following shunt revision.

PURPOSE: To analyze the feasibility of 2D-perfusion angiography (2D-PA) to quantify flow and perfusion changes pre- and post-transjugular intrahepatic portosystemic shunt (TIPS) revision. MATERIALS AND METHODS: Fifteen consecutive patients (54 ± 14 years, seven men and eight women) scheduled for TIPS revision were included in this study. To quantify flow and perfusion changes caused by TIPS revision, digital subtraction angiography (DSA) series acquired during the revision were post-processed using a dedicated software. Reference region-of-interest (ROI) in the main portal vein (input function) and target ROIs in the TIPS lumen, the liver parenchyma and in the right atrium were placed in corresponding areas on DSA pre- and post-TIPS revision. 2D-PA evaluation included time to peak (TTP), peak density (PD), and the area under the curve (AUC) assessment. The ratios of reference ROI to target ROIs pre- and post-TIPS revision were calculated (TTPparenchyma/TTPinflow, PDparenchyma/PDinflow, AUCparenchyma/AUCinflow, TTPTIPS/TTPinflow, PDTIPS/PDinflow, AUCTIPS/AUCinflow, TTPatrium/TTPinflow, PDatrium/PDinflow, and AUCatrium/AUCinflow). Pressure measurements pre- and post-TIPS revision were performed and correlated to the 2D-PA parameters. Reproducibility of 2D-PA was assessed by the intra-class correlation coefficient (ICC). RESULTS: The portosystemic pressure gradient was significantly reduced following TIPS revision (17.1 ± 6.3 vs. 8.9 ± 4.3 mmHg; p < 0.0001). PDTIPS/PDinflow (0.22 vs. 0.35; p = 0.0014) and AUCTIPS/AUCinflow (0.24 vs. 0.39; p = 0.0012) increased significantly. Likewise, PDatrium/PDinflow (0.32 vs. 0.78; p = 0.0004) and AUCatrium/AUCinflow (0.3 vs. 0.79; p < 0.0001) increased, whereas PDparenchyma/PDinflow decreased significantly (0.14 vs. 0.1; p = 0.0084). Pressure gradient changes correlated significantly with the increase in PDatrium/PDinflow (r = - 0.77, p = 0.0012) and AUCatrium/AUCinflow (r = - 0.76, p = 0.0018). ICC of the 2D-PA parameters was in the range of 0.88-0.99. CONCLUSION: 2D-PA offers a feasible approach to quantify flow and perfusion changes during TIPS revision. Therefore, 2D-PA may be a valuable amendment to mere pressure measurements.

Assessment and optimization of liver volume before major hepatic resection: Current guidelines and a narrative review.

Post hepatectomy liver failure (PHLF) remains a significant cause of morbidity and mortality after major liver resection. Although the etiology of PHLF is multifactorial, an inadequate functional liver remnant (FLR) is felt to be the most important modifiable predictor of PHLF. Pre-operative evaluation of FLR function and volume is of paramount importance before proceeding with any major liver resection. Patients with inadequate or borderline FLR volume must be considered for volume optimization strategies such as portal vein embolization (PVE), two stage hepatectomy with portal vein ligation (PVL), Yttrium-90 radioembolization, and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). This paper provides an overview of assessing FLR volume and function, and discusses indications and outcomes of commonly used volume optimization strategies.

Greater hypertrophy can be achieved with associating liver partition with portal vein ligation for staged hepatectomy compared to conventional staged hepatectomy, but with a higher price to pay?

BACKGROUND: Associating liver partition with portal vein ligation for staged hepatectomy (ALPPS) and conventional staged hepatectomy (CSH) are options for patients with unresectable liver tumors due to insufficient future liver remnant (FLR). METHODS: A retrospective comparison of clinical data, liver volumetry and surgical outcomes between 10 ALPPS and 29 CSH patients was performed. RESULTS: Patient demographics and disease characteristics were similar between both groups. ALPPS induced superior FLR growth (ALPPS vs. CSH, 48.1% (IQR 39.4-96.9%) vs. 11.8% (IQR 4.3-41.9%), p = 0.013). However, post-operative day 5 international normalized ratio (INR) (ALPPS vs. CSH, 1.6 (IQR 1.5-1.8) vs. 1.4 (IQR 1.3-1.6), p = 0.015) and rate of post-hepatectomy liver failure (ALPPS vs. CSH, 25 vs. 0%, p = 0.032) was higher in the ALPPS group. 90-day mortality (ALPPS vs. CSH, 12.5% vs. 0%, p = 0.320) was similar in both groups. CONCLUSION: ALPPS was superior in inducing FLR growth but associated with increased post-hepatectomy liver failure compared to CSH.

Assessment of liver regeneration after associating liver partition and portal vein ligation for staged hepatectomy: a comparative study with portal vein ligation.

BACKGROUND: To investigate the diagnostic value of diffusion kurtosis imaging (DKI) and diffusion-weighted imaging (DWI) in assessing liver regeneration after associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) compared with portal vein ligation (PVL). METHODS: Thirty rats were divided into the ALPPS, PVL, and control groups. DKI and DWI were performed before and 7 days after surgery. Corrected apparent diffusion (D), kurtosis (K) and apparent diffusion coefficient (ADC) were calculated and compared, radiologic-pathologic correlations were evaluated. RESULTS: The volume of the right median lobe increased significantly after ALPPS. There were larger cellular diameters after ALPPS and PVL (P = 0.0003). The proliferative indexes of Ki-67 and hepatocyte growth factor were higher after ALPPS (P = 0.0024/0.0433). D, K and ADC values differed between the groups (P = 0.021/0.0015/0.0008). A significant correlation existed between D and the hepatocyte size (r = -0.523), no correlations existed in ADC and K (P = 0.159/0.111). The proliferative indexes showed moderate negative correlations with ADC (r = -0.484/-0.537) and no correlations with D and K (P = 0.100-0.877). DISCUSSION: Liver regeneration after ALPPS was effective and superior to PVL. DKI, especially the D map, may provide added value in evaluating the microstructure of liver regeneration after ALPPS, but this model alone may perform no better than the standard monoexponential model of DWI.